AlpHa Measurement Solutions | Temperature Sensors

Temperature Sensors

Temperature is an important consideration in water quality monitoring when measured in conjunction with parameters such as pH, conductivity, and dissolved oxygen. Changes in temperature play a critical factor with regards to the chemical and physical properties of water. Examples include biological growth, activity changes in environmental applications, minerals being dissolved in ground or surface water applications, reduction in water quality, and an increase in contaminants in industrial processes. It is important to understand the specific application and how temperature plays its part.  
Common temperature sensors in use are either a negative temperature coefficient (NTC) device, commonly referred to as a “thermistor”, or a resistive temperature detector (RTD). Both are resistive measurements, but the NTC has a negative temperature coefficient, whereas the RTD has a positive correlation between resistance and temperature. Once housed, cabled, and a connector added, the NTC or RTD becomes a temperature sensor. The measurement of temperature in aqueous samples typically involves either an integrated temperature sensor inside a sensing electrode or one that is stand-alone as a separate temperature sensor. Thermistor compatibility with instrumentation is critical; therefore, when reviewing the application and design, there are core considerations for choosing the correct temperature sensor:
  • Thermistor Compatibility with Desired Instrument
  • Accuracy and Range
  • Response Time
  • Form Factor for Mechanical Insertion 
AlpHa Measurement Solutions can integrate the desired temperature sensor, that fits the design requirements, with any parameter requested. For measurements that involve electronics, AlpHa has included temperature compensation to correct the output characteristics according to its influence of the operating temperature. For stand-alone temperature sensors, AlpHa has different options for form factor, housing materials, thermistors, and connectors.